As the light-emitting diode (LED) is becoming more and more common, most recent illumination apparatuses use the LED as a light source. The illuminating functions of the lamp on the market nowadays are quite limited. A lamp having two purposes can emit only white light and yellow light for general illumination and for night illumination. Regardless of whether a lamp is used for general illumination or night illumination, the color, brightness, and the chroma of the emitted light cannot be changed, so the functions of traditional lamps are quite limited.